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Diamond Detectors. Christoph Kurfuerst BE-BI-BL Ewald Effinger BE-BI-BL. Outline. Why Diamond Detectors Technical information about Diamond Detectors Measurement results Diamond as cryogenic Beam Loss Monitor ? Conclusions. Why Diamond Detectors. Measurement of fast beam losses
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Diamond Detectors Christoph Kurfuerst BE-BI-BL EwaldEffinger BE-BI-BL
Outline • Why Diamond Detectors • Technical information about Diamond Detectors • Measurement results • Diamond as cryogenic Beam Loss Monitor? • Conclusions
Why Diamond Detectors • Measurement of fast beam losses • ns response time • Bunch by bunch structure • Radiation tolerant detector type • Low maintenance • Constant operating conditions • Small dimensions • Easier positioning in areas with space limitation • Well known response signal • Detector tested under many conditions for verification of the performance • High dynamic range ~ 8 order of magnitude • Linear response to particle flux
Diamond Detector Types pCVDsCVD pCVD = polycrystalline Chemical Vapor Deposition (10x10 mm2 x 0.5 mm) sCVD= single-crystal Chemical Vapor Deposition (5x5 mm2 x 0.5 mm)
BLMD (type Cividec) Detector AC/DC Splitter 2 GHz Amplifier • pCVD detector: with high voltage and signal connection • AC-DC-Splitter: to separate AC signal current from DC leakage current • 2 GHz / 20 dB Broadband Amplifier ( various amplifier available ) • Internal HF copper housing and aluminum housing for mechanical protection
Principle of Cividecdetector Ch1 Scope Ch2 Diamond Detector • Detector, splitter and amplifier on support plate • High and low voltage supply • Controlled via ET-7026 Ethernet Controller • 1 GHz Scope from LeCroy • Readout via FESA Application from S.B. Pedersen ~ 100m CK50 6 dB Power splitter
BLMD (BCM1F CMS / DESY Zeuten) • sCVD detector: mounted on the analogue optical link • analogue optical link mounted on support PCB including radiation tolerant voltage regulator and test pulse generator • Housing with Burndy-8 (for high and low voltage supply) • E-2000 connector for optical signal
Principle of BCM1F Detector discription • sCVD detector with a bias voltage 125 V • Fast amplifier (rad tolerant) • Analogue optical link LLD form the MIC • Optical single mode fiber of around 2km Analogue Receiver (865-RA-04) • Optical receiver from CMS • ADC CEAN V1721 • LTD CEAN V814 • TDC CEAN V767 • Bridge CEAN V2718 • BOBR for timing signals • PC for data treatment
Measurement results Cividec Measurement from CNGS Detector (16/11/2011 -- 7.24AM) Detector 4 (pit 1) with 40dB AC amplifier Detector 5 (pit 2) with 40dB AC amplifier Extraction trigger Detector 1 (pit 1) without amplifier Detector 2 (pit 1) without amplifier Detector 3 (pit 2) with 20dB AC amplifier Extraction trigger
Measurement results Cividec Measurement from CNGS Detector (16/11/2011 -- 7.24AM) Pic 1. Detector 2 (pit 1) without amplifier (complete extraction) Pic 2. Detector 2 (pit 1) without amplifier ( zoom of rising edge) Pic 3. Detector 2 (pit 1) without amplifier (zoom 5ns structure visible)
Measurement results BCM1F Arrival Time Histogram from Losses downstream at Collimator in Point 8 Losses from beam and interaction 50 ns bunch spacing Losses from beam
CryoBLM Project • At IR: ability to measure energy deposition in coil limited because of debris from collisions • Problem: signal from debris with similar height as simulated beam losses in steady state case • Solution: placing detectors closer to losses (inside cold mass of the magnet, 1.9 K) • Further possible amelioration: injection area, behind collimators • Detectors under test: Diamond, Silicon and liquid helium chamber
Question: Does diamond work at 1.9 K for particle detection?
Beam test area with cryogenics • Intro Preamplifiers Cryostat Dewar Detectors inside cryostat Vacuum pump Electronics Beam PC Oscilloscope
Single Particle pulse Detection of minimum ionising particles possible with diamond at liquid helium temperatures
Collected charge per particle Estimated: 3.79 fC
Collected charge per spill Measurements in DC mode, as needed for final application
Conclusion • Diamond proves good properties for BLM application • Diamond usable for particle detection at liquid helium temperatures • Open questions: • Radiation hardness of material at 1.9 K (tests planed for 2012) • Polarisation at low temperatures might be issue for final application
Acknowledgments • Erich Griesmayerform CIVIDEC for electronics, plots and pictures • Wolfgang Lange from DESY Zeuten for detector pictures • Elena Castro from DESY Zeuten for plots • Stephane Bart Pedersen form BI/SW for plots • Vladimir Ereminfor semiconductors holder and general help in many ways • Thomas Eiseland his team for cryogenics • Heinz Perneggerfor analysis program and the sCVD • HendrikJansen for material and discussions